Here are the sensitivity and linearity measurements done at 2,83V from the listening spot, ~2,5m away from the speakers. Both are done completely without eq, including no 6dB/oct dipole compensation, there is just LR4 low pass at 800Hz.

Im impressed with the output and efficiency. A row of 8's or 10's with an RD 50 may be the way I go.

Here is my latest. Not finished obviously but sounding very very nice. The tweeter is currently on the rear (wanted to audition for a while before cutting holes) The phase plugs shown are only temp. Waiting on the return of more favourable weather to finish.